Graphical user interfaces (GUIs) allow users to interact with electronic devices, such as computers and mobile devices, through graphical icons and visual indicators, as opposed to text-based interfaces, which rely on typed command labels or text navigation. GUIs have traditionally relied on a combination of navigation-based input, such as through the use of computer mice, trackpads, etc., and text-based input through keyboards.
In recent years, voice recognition technology has improved to the point where interaction with electronic devices using voice is now a credible alternative to navigation-based and text-based input. As devices get smaller and smaller and voice-based input becomes more and more prevalent, there has been a movement away from direct interaction with an electronic device using one's own hands and fingers. There are a number of people, however, who long for the day when using a pen or pencil and paper was the predominant way to communicate. Additionally, there are still certain types of actions in a user interface that are easier for humans to communicate using more freeform methods of expression, such as combinations of text and drawings, that are not possible using existing GUIs.